Manganese distribution

Glenn C. Soth. Was manganese distribution studied I have encountered an Oklahoma coal (medium volatile) with manganese high enough to interfere with the usual Eschka sulfur determination. 

Yang, M., and Sanudo-Wilhelmy, S.A. (1998) Cadmium and manganese distributions in the Hudson River estuary Interannual and seasonal variability. Earth Planet. Sci. Lett. 160, 403-418. 

H. SelLner, K. Hametner, D. Gunther, D. Seebach, Manganese distribution in polystyrene beads prepared by copolymerization with cross-linking dendritic salens using laser ablation inductively coupled plasma mass spectrometry, /. Gatal. 215 (2003) 87. 

Lai JC, Minski MJ, Chan AW, et al. 1981. Brain regional manganese distribution after chroitic manganese treatment. Biochem Soc Trans 9 228. 

YamadaM, Ohno S, Okayasu I, et al. 1986. Chronic manganese poisoning A neuropathological study with determination of manganese distribution in the brain. Acta Neuropathol (Berl) 70 273-278. 

Michard, G. (1971). Theoretical model for manganese distribution in calcareous sediment cores. J. Geophys. Res. 76, 2179-2186. 

White GN, Dixon JB (1996) Iron and manganese distribution in nodules from a young Texas vertisol. Soil Sci Soc Amer J 60 1254-1262... 

Fig. 4. Copper and manganese distribution in geoiogicai samples showing three clusters with differing proportions of each metal.

Crossgrove JS, Allen DD, Bukaveckas BL, Rhineheimer SS, and Yokel RA (2003) Manganese distribution across the blood-brain barrier. I. Evidence for carrier-mediated influx of manganese citrate as well as manganese and manganese transferrin. Neurotoxicology 24 3—13. 

The kinetics of the consecutive reaction (4) could be found, however, from the resulting distribution of manganese over the silica granules. An example of such a distribution as obtained from electron microprobe analysis is shown in Fig. 6. The qualitative shape of the distribution indicates that reaction (4) is influenced by both kinetic and diffusion effects. In order to further extract quantitative information from the manganese distributions we have assumed that the kinetics of reaction (4) can be approached by a first-order dependence in manganese and a zero—order dependence for the other components. With these assumptions one can make use of the Thiele concept of diffusion-limited reactions [11]. 

Manganese is the third most abundant transition metal, and is widely distributed in the earth s crust. The most important ore is pyrolusite, manganese(IV) oxide. Reduction of this ore by heating with aluminium gives an explosive reaction, and the oxide Mn304 must be used to obtain the metal. The latter is purified by distillation in vacuo just above its melting point (1517 K) the pure metal can also he obtained by electrolysis of aqueous manganese(II) sulphate. 

Manganese minerals are widely distributed oxides, silicates, and carbonates are the most common. The discovery of large quantities of manganese nodules on the floor of the oceans may become a source of manganese. These nodules contain about 24% manganese together with many other elements in lesser abundance. 

Manganese is widely distributed throughout the animal kingdom. It is an important trace element and may be essential for utilization of vitamin Bl. 

The United States consumption of manganese is distributed between three industries iron and steelmaking, where 88% of the Mn is consumed the manufacture of batteries, where 7% is used and chemical usage, which accounts for the remaining 5%. United States manganese demand is shown in Figure 12. 

Manganese. The adult human body contains ca 10—20 mg of manganese (124,125), widely distributed throughout the body. The largest Mg " concentration is in the mitochondria of the soft tissues, especially in the Hver, pancreas, and kidneys (124,126). Manganese concentration in bone varies widely with dietary intake (126) (see Table 10). 

The physical and mechanical properties of steel depend on its microstmcture, that is, the nature, distribution, and amounts of its metaHographic constituents as distinct from its chemical composition. The amount and distribution of iron and iron carbide determine most of the properties, although most plain carbon steels also contain manganese, siUcon, phosphoms, sulfur, oxygen, and traces of nitrogen, hydrogen, and other chemical elements such as aluminum and copper. These elements may modify, to a certain extent, the main effects of iron and iron carbide, but the influence of iron carbide always predominates. This is tme even of medium alloy steels, which may contain considerable amounts of nickel, chromium, and molybdenum. 

Mechanical properties depend on the alloying elements. Addition of carbon to the cobalt base metal is the most effective. The carbon forms various carbide phases with the cobalt and the other alloying elements (see Carbides). The presence of carbide particles is controlled in part by such alloying elements such as chromium, nickel, titanium, manganese, tungsten, and molybdenum that are added during melting. The distribution of the carbide particles is controlled by heat treatment of the solidified alloy. 

At present, chlorine dioxide is primarily used as a bleaching chemical in the pulp and paper industry. It is also used in large amounts by the textile industry, as well as for the aching of flour, fats, oils, and waxes. In treating drinking water, chlorine dioxide is used in this country for taste and odor control, decolorization, disinfection, provision of residual disinfectant in water distribution systems, and oxidation of iron, manganese, and organics. The principal use of chlorine dioxide in the United States is for the removal of taste and odor caused by phenolic compounds in raw water supplies. 

Figure 3. Schematic drawing of the crystal structure of f-MnOj. The manganese atoms are randomly distributed in the octahedral voids of the hexagonal dose packing of oxygen atoms (adapted from [47]).

The manganese atoms are distributed in a more or less ordered manner at the slightly distorted octahedral voids in the hexagonally close-packed oxygen atoms (as described above). 

Aeration towers are often simply constructed wooden towers with or without the benefit of a forced-air draft, over which the well water is distributed. Typically, the tower holds 8 to 10 trays, each with a 3- to 4-inch (7.6-10.2 cm) bed depth of volcanic lava or coke media to provide the total 30 to 36" (76-91 cm) depth required. The lava or coke acts as a catalyst for the further precipitation of iron and manganese salts. These salts can be readily oxidized provided there is sufficient alkalinity present. If in doubt, ensure a minimum of 120 to 150 ppm total alkalinity (T Aik or M Aik) as CaC03. 

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